Synthesis of stereoisomeric crown ethers composed of cis- and trans-2,5-bis(hydroxymethyl)tetrahydrofuran units and their selective transport of alkali metal cations through liquid membranes
Enantiomer recognition of crown ethers and open-chain polyethers containing the trans-tetrahydrofuran-2,5-diylbis(methylene) subunit as the chiral centre
The opticallyactive open-chain polyethers (2)–(6) incorporating a trans-tetrahydrofuran-2,5-diylbis(methylene) molecular framework of C2 symmetry as the chiral subunit were prepared, and their enantiomer recognition behaviour, as well as that of crown ethers (7)–(12) containing the same chiral subunit, was examined.